Why are the X and Y chromosomes commonly referred to as the sex chromosomes?

Astudent reads the following text in a science book: scientific evidence tells us that the cause of earths four seasons is the tilt of earth as it revolves around the sound the student is instructed to illustrate this information in a science book. how will the student illustrate winter in the northern hemisphere? a. earths northern hemisphere will tilt away from the sun. b. earths northern hemisphere will tilt toward the sun. c. earths orbit will be farther away than from the sun d. earths southern hemisphere will tilt away from the sun.

What are some natural processes that represent physical and chemical changes?

Which of the following types of stars are dim but can have high surface temperatures? giants main sequence stars supergiants dwarfs